1. Field of the Invention
The invention pertains to conversion kits for modifying standard wheelchairs having fixed seats to permit seat tilting and seat back reclining between infinitely variable positions.
2. Description of the Related Art
Many seriously handicapped patients spend the majority of their waking hours in wheelchairs. Conventional wheelchairs utilize fixed seats, and while some wheelchairs having fixed seats permit limited reclining of the seat backs, the spending of long hours in a relatively non-adjustable wheelchair produces body sores, muscle aches and spasms, and is generally uncomfortable for the patient due to the inability of the pressure points on the patient's body to be periodically varied by the shifting of the patient's weight as would occur if the seat position was adjustable.
Wheelchairs having tiltable seats and reclinable backs are available. However, such adjustable wheelchairs are very expensive and are not economically available to many patients who would benefit from such devices.
Efforts have been made to provide economically feasible wheelchair constructions having adjustable seat functions. For instance, U.S. Pat. No. 4,968,051 discloses a wheelchair having a reclinable seat back. U.S. Pat. No. 4,085,946 discloses a wheelchair which can be converted to a dental chair, and U.S. Pat. No. 4,565,385 discloses a conventional wheelchair used in conjunction with support apparatus which permits the wheelchair to be tilted to add to the patient comfort.
U.S. Pat. No. 5,044,647 discloses a wheelchair modification kit which may be retrofitted to existing wheelchairs to permit the seat to be pivoted, and limited angular adjustment between the seat and seat back is also possible. This patent deals with the same problem addressed by the instant invention, but the apparatus shown in U.S. Pat. No. 5,044,647 is expensive to manufacture and assemble to an existing wheelchair, and is not considered to meet the strength and rigidity requirements necessary.